Deleted in liver cancer 1 suppresses the growth of prostate cancer cells through inhibiting Rho-associated protein kinase pathway

Objective: Deleted in liver cancer 1 (DLC1) is a GTPase-activating protein that is reported as a suppressor in certain human cancers. However, the detailed biological function of DLC1 is still unclear in human prostate cancer (PCa). In the present study, we aimed to explore the function of DLC1 in PCa cells. Methods: Silencing and overexpression of DLC1 were induced in an androgen-sensitive PCa cell line (LNCaP) using RNA interference and lentiviral vector transduction. The Cell Counting Kit-8 assay was performed to determine cell proliferation. The cell cycle was examined by performing a propidium iodide staining assay. Results: Our results indicated that DLC1 overexpression markedly suppressed the proliferation and cell cycle progression of LNCaP cells. Moreover, DLC1 expression was negatively correlated with Rho-associated protein kinase (ROCK) expression in LNCaP cells. Importantly, this study showed that the ROCK inhibitor Y27632 restored the function of DLC1 in LNCaP cells and reduced the tumorigenicity of LNCaP cells in vivo. Conclusion: Our results indicated that DLC1 overexpression markedly suppressed the proliferation and cell cycle progression of PCa cells and negatively correlated with ROCK expression in PCa cells and tissue

Cyclic volatile methylsiloxanes (cVMSs) in the air of the wastewater treatment plants in Dalian, China - Levels, emissions, and trends

Passive air samplers comprising sorbent-Tenax-TA thermal desorption tubes were applied for monitoring cyclic volatile methyl siloxanes (cVMSs) in the air above the aeration tanks of eight wastewater treatment plants (WWTPs, including five “open” and three “close” plants) in Dalian, China. The aim was to investigate the inputs of cVMSs from WWTPs to the air throughout a year (June 2016–July 2017). The ∑cVMS concentrations were averaged at 3.14 ± 6.84 μg·m³ with D5 as the dominant compound (contributing to 63.8% of the ∑cVMS concentration). The annual average concentrations of D4, D5, and D6 in the air of the “close” WWTPs were 5.33 ± 4.63, 13.4 ± 14.4, and 1.05 ± 1.47 μg·m³, and 1.31 ± 1.29, 1.57 ± 2.01, and 0.301 ± 0.340 μg·m³ in the air from the “open” WWTPs, respectively. For both the close and open aeration tanks, the concentration of ∑cVMSs was the highest in summer and the lowest in winter, showing a significant correlation with ambient temperature (linear regression; p < 0.01). A simplified Gaussian dispersion model and a single chamber model were introduced to estimate annual emissions (kg·yr) of cVMSs from “open” and “close” WWTPs, ranging from 86.9 to 165 kg yr and from 203 to 278 kg yr, respectively. Examining the relationship between the per capita emissions of cVMSs and average property prices, our results indicated that a greater amount of personal care products were used/discharged by people with relatively higher socioeconomic status

Atomistic Investigation of the Effects of Different Reinforcements on Al Matrix Composite

In this work, we studied the effects of different reinforcements on a metal matrix composite (MMC) using molecular dynamics (MD) simulations, where graphene was chosen as the two-dimensional (2D) material and diamond was selected as the three-dimensional (3D) material. Sintering and tensile processes were conducted on the MMC models containing reinforcements of various sizes, and the effects of reinforcements with the same surface area were compared. The results indicated that the 2D material was more beneficial for sintering at the heating stage, producing a higher-density structure. The volume of Al atoms fell from 752 to 736 nm3 as the graphene size in the composite system increased. However, a slight increase from 749 to 755 nm3 was observed when the diamond radius was small. Converted to relevant metrics in the experiments, the density of the composite reached 2.84 g/cc with a 3.3 wt.% addition of single-layer graphene (SLG) and 2.87 g/cc with a 15.4 wt.% addition of diamond, and the results were slightly higher than the experimental reports. Both SLG and diamond could reduce the number of arranged Al atoms from 43,550 to approximately 35,000, and bilayer graphene (BLG) with the largest size could further decrease the number of arranged atoms to nearly 30,000, implying that grain refinement could be obtained by increasing the surface area of reinforcements. Considering the scale of these models, the reinforcement size and pore location in the initial structures were deemed to have an impact on the mechanical properties. The composite with the largest proportion of SLG showed an increase of more than 1.6 GPa in tensile strength; however, BLG showed a significant drop of 1.9 GPa when stretched in the normal direction, as the large interlayer space acted as a large hole in tension. The diamond size did not appear to affect the strengthening effects. Nevertheless, the elongation values of composites with graphene were generally 35% higher than the Al-diamond composites

Preparation and Properties of Electrodeposited Ni-B-Graphene Oxide Composite Coatings

With the rapid development of modern industries, the surface quality and performance of metals need to be improved. Composite electrodeposition (co-deposition) has evolved as an important technique for improving the surface performance of metal materials. Herein, a new type of graphene oxide (GO)-reinforced nickel–boron (Ni-B) composite coating was successfully prepared on a 7075 aluminum (Al) alloy by co-deposition. Characterization revealed a significant improvement in the mechanical and anti-corrosion properties of the composite with the incorporation of GOs. The composite showed a rougher, compact, cauliflower-like morphology with finer grains, a higher hardness (1532 HV), a lower rate of wear (5.20 × 10−5 mm3∙N−1∙m−1), and a lower corrosion rate (33.66 × 10−3 mm∙y−1) compared with the Ni-B alloy deposit (878 HV, 9.64 × 10−5 mm3∙N−1∙m−1, and 116.64 × 10−3 mm∙y−1, respectively). The mechanism by which GOs strengthen the Ni-B matrix is discussed

Streamflow changes in the headwater area of Yellow river, NE Qinghai-Tibet plateau during 1955–2040 and their implications

Human activities have substantially altered present-day flow regimes. The Headwater Area of the Yellow River (HAYR, above Huanghe’yan Hydrological Station, with a catchment area of 21,000 km2 and an areal extent of alpine permafrost at ~86%) on the northeastern Qinghai-Tibet Plateau, Southwest China has been undergoing extensive changes in streamflow regimes and groundwater dynamics, permafrost degradation, and ecological deterioration under a warming climate. In general, hydrological gauges provide reliable flow records over many decades and these data are extremely valuable for assessment of changing rates and trends of streamflow. In 1998–2003, the damming of the Yellow River by the First Hydropower Station of the HAYR complicated the examination of the relations between hydroclimatic variables and streamflow dynamics. In this study, the monthly streamflow rate of the Yellow River at Huanghe’yan is reconstructed for the period of 1955–2019 using the double mass curve method, and then the streamflow at Huagnhe’yan is forecasted for the next 20 years (2020–2040) using the Elman neural network time-series method. The dam construction (1998–2000) has caused a reduction of annual streamflow by 53.5–68.4%, and a more substantial reduction of 71.8–94.4% in the drier years (2003–2005), in the HAYR. The recent removal of the First Hydropower Station of the HAYR dam (September 2018) has boosted annual streamflow by 123–210% (2018–2019). Post-correction trends of annual maximum (QMax) and minimum (QMin) streamflow rates and the ratio of the QMax/QMin of the Yellow River in the HAYR (0.18 and 0.03 m3·s−1·yr−1 and −0.04 yr−1, respectively), in comparison with those of precorrection values (−0.11 and −0.004 m3·s−1·yr−1 and 0.001 yr−1, respectively), have more truthfully revealed a relatively large hydrological impact of degrading permafrost. Based on the Elman neural network model predictions, over the next 20 years, the increasing trend of flow in the HAYR would generally accelerate at a rate of 0.42 m3·s−1·yr−1 . Rising rates of spring (0.57 m3·s−1·yr−1) and autumn (0.18 m3·s−1·yr−1) discharge would see the benefits from an earlier snow-melt season and delayed arrival of winter conditions. This suggests a longer growing season, which indicates ameliorating phonology, soil nutrient availability, and hydrothermal environments for vegetation in the HAYR. These trends for hydrological and ecological changes in the HAYR may potentially improve ecological safety and water supplies security in the HAYR and downstream Yellow River basins.</p